A headset for voice communications (e.g., a Bluetooth™ headset, a DECT headset or a wired headset, such as a USB headset) typically contains a loudspeaker for reproducing a far-end audio signal at one of the user's ears and a voice microphone for receiving the headset wearer's speech.
The loudspeaker is positioned at one or both of the headset wearer's ears, and the voice microphone is arranged within the headset to be positioned during use to receive the user's speech with an acceptably high signal-to-noise ratio. The voice microphone is typically located, for example, within a headset housing, an ear-cup, in a headset boom or other protrusion that extends from such a housing toward the user's mouth, or on a cord that carries audio signals to and from the cellular telephone.
A headset may attenuate sound from the environment around the headset wearer by an ear-cup or an active noise-cancelling technique such that the headset wearer is protected from disturbing sounds around him/her. A headset may also attenuate sound from the environment around the headset wearer before transmission to a far end e.g. in case the voice microphone is a directional microphone e.g. implemented using beamforming.
It may happen that a headset attenuates not only sound from the environment but also the headset wearer's own speech. This causes problems for the headset wearer to adapt his speech and in particular how loud he/she talks since he/she cannot hear him-/herself.
To overcome that problem, the headset may be configured with a feedback path whereby a small amount of the headset wearer's own speech (picked up by the voice microphone) is fed back to the headset wearer's ear via the loudspeaker. This is also known as a side-tone. The side-tone is often attenuated or amplified to reflect the amount of feedback a person will perceive when speaking in a room without wearing a headset.
The further away from the headset wearer's mouth the voice microphone is situated, the more sound from the surroundings relative to speech from the headset wearer will be picked up and reproduced by the loudspeaker in his/hers ears. This may be a problem since it is often preferred to dispense with microphone booms or similar extensions.
It should be noted that conventionally sometimes a loudspeaker in a headset is denoted a receiver.